Question

The resistance of a conductor $1{mm}^2$ in cross section and $20m$ long is $0.346\Omega$. Determine the specific resistance of the conducting material.

Answer 1

$R=\rho \frac{l}{a}$

$\rho =R\frac{a}{l}$

Here , $a$ = $1$ $m{m}^2$

$l$ = $20$ m

and $R$ = $0.346\Omega$

Therefore ,

$\rho$ = $\left(0.346\right)\frac{{10}^{-4}}{20}$ $\Omega m$

= $1.73\times {10}^{-6}$ $\Omega m$